76 A LICHEN. 



LABORATORY WORK. 



GROSS STRUCTURE. 



With a piece of the support on which is a piece of the Lichen 

 observe: 



1. The color of the Lichen, both of its upper surface and of 

 any parts of the under surface that can be seen. Com- 

 pare the color of wet and dry specimens. 



2. Its form. 



3. How it is attached to its support. 



4. The fruiting cups (apoihecia) of various sizes. 



5. Make a sketch showing the general form of the Lichen, its 

 relation to its support, and the apothecia. 



MINUTE STRUCTURE. 

 I. VEGETATIVE CHARACTERS. 



Select a piece of the body that has been moistened, care- 

 fully dissect and mount it, and observe: 



1. The two elements, the Algae and Fungi, that together 

 compose the Lichen body. 



2. The form and structure of each of these elements, and 

 their similarity to any of the plants previously studied. 



3. Cases where the threads of Fungi are closely wrapped 

 about the algal cells. 



4. Whether there is any evidence that the Algae are suffering 

 from their close contact with the Fungi. 



5. Make drawings showing the two elements and their rela- 

 tion to one another. 



By means of a carefully prepared cross-section of the Lichen 

 body observe: 



6. The layer formed of Fungus alone, composing the outer 

 regions. 



